I really think this pistol could be a Glock killer, or at the very least challenge Glock's throne for the most widely issued and owned pistol.
The removable fire control unit is very compelling to police departments because damage to the frame can be corrected by simply swapping out a sub-$30 unserialized part. Not having to worry about Officer Dummy accidentally shooting himself on the foot when he disassembles it is also a nice reason to switch from Glocks.
The P320 is less expensive than the Glock and already comes stock with features that Glock owners pay extra to get done after the fact. Undercut trigger guard, a normal trigger without the stupid safety lever on it, front slide serrations, normal 3 dot sight in contrast or tritium instead of the stupid U shaped rear sight that they still put on Glocks for god knows why, no finger grooves, etc etc.
Once this gun gains popularity from the Army selecting it, and more companies start offering aftermarket support and cheaper magazines, there will really be no reason for anyone to want a Glock.